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PostPosted: June 1, 2012, 12:43 pm 
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To throw another option into the pile.

I have seen where a few hot-rod style cars have either ran split front axle ( 2 with off sets to line up the front spindles) also have seen where they have cut a tube style axle in the center and mount both halves at a cent pivoit point. The problem I would see with using traditional spindles would be with the suspension movement and caster and camber gain.

With going with Cheap racers set-up and using later model spindle and ball joints you may be able to account for this.

On our 27 we used a Superbell drop axle and split wish-bones along with torsoin bars and shocks.
It is not the greats set-up for auto-cross or track driving, but is good for normal driving.


Also have seen a mock up of a early style ford spindle that used C-5 style hubs, so the person could use newer and larger brakes - this was at a show we went to a while back, not sure how it was done or how well it worked.

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PostPosted: June 7, 2012, 1:15 pm 
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Driven5 wrote:
Clever. It seems to me that this would still experience some amount of bump steer during non-uniform suspension movements liek one wheel bumps or as body roll angle changes...Or am I thinking about some part of it the wrong way?


A-ha, he says!

As the chassis has been locked down on the jig while I have been cobbling up and understanding this steering setup, I have only had access to limited axle roll.

Today I popped the chassis out of the jig and put it up in the air enabling me to get full axle roll. I discovered that 'Pivot 5' needs to be close to the roll center height (preferably a little above) otherwise you do get some roll steer as the RC and 'Pivot 5' are rotating on different fulcrum points.

This would be fine for a fixed RC fulcrum such as Watts link, A-link etc. but maybe not so good for RC's that move in height such as a Panhard rod.


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PostPosted: June 7, 2012, 4:02 pm 
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are you doing this just to say you have done it or to confuse a scrutineer, because i went to the grocery store yesterday just to say i'd been, it seems to need a lot of links and ball joints to make work and is heavy.

have you looked at a morgan sliding pillar front end, its soooo simple and weighs hardly anything.

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PostPosted: June 8, 2012, 12:42 pm 
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john hennessy wrote:
have you looked at a morgan sliding pillar front end, its soooo simple and weighs hardly anything.
Much rather have a well designed beam than that rubbish. :ack:

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PostPosted: June 8, 2012, 1:55 pm 
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john hennessy wrote:
are you doing this just to say you have done


I'm a believer in an advanced beam system.

john hennessy wrote:
it seems to need a lot of links and ball joints


That's relative to what performance it offers.

john hennessy wrote:
and is heavy.


Oh? How much does it weigh?

john hennessy wrote:
have you looked at a morgan sliding pillar front end, its soooo simple and weighs hardly anything.


Ironic you should reccomend a system that has similar steering issues to get around. Besides that, it's a pillar of, err sorry, pile of shite - stiction, maintainence and no camber gain being the main issues.

Oh and it's a misnomer too, it's actually a sliding axle, a major English magazine did a test in the 50's of a Morgan and incorrectly named it "sliding pillar" and customers came in asking about it using this term so often the name stuck.


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PostPosted: June 8, 2012, 3:53 pm 
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having worked on these for many years, it is a sliding pillar, the pillar being a long king pin with the spring above the spindle assy. the wheel stays still 'cos it's on the ground and the pillar slides up and down with the car.

yes they do have there short commings with no camber change and are prone to bending, the standard rectification for this is two braces back to the chassis from the top and bottom of the king pin assy.

well i could say the same about what you are proposing , its got all sorts of failure points, weighs a ton and will not out perform a normal independant suspension system, but i would not go as far as saying it's a pile of shite, old fashoned that it may be, just compare the unsprung weight of the Morgan system to that beam thing and who wins? the only unsprung weight is the spindle assy.

i will say at this point, that i personally prefer an independant system over the sliding pillar, i have done this to a morgan, but i would prefer a beam axle with cart springs over your design, even if it was made of wood.

as far as being a believer in advanced beam systems, they may certainly be usfull on a big rig or a 4x4 but a light sports car of any type, is debateable, how much does it weigh as a pecentage of the overall chassis?

some people believe the world is flat and was made in 7 days, thats their right so who am i to comment, it was just a suggestion.

to use your word again "eat shite, a million flys can't be wrong"

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PostPosted: June 8, 2012, 5:19 pm 
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john hennessy wrote:
are you doing this just to say you have done it or to confuse a scrutineer, because i went to the grocery store yesterday just to say i'd been, it seems to need a lot of links and ball joints to make work and is heavy.
I'm more wondering why one would want to "maintain a flat footprint" (keep a constant camber, ignoring caster gain which most [all] front suspensions have) when it is commonly agreed upon that modern tires have more cornering force with varying cambers depending on the cornering forces created by during high speed cornering.

Yes, you could preset this solid axle design to have good high speed cornering but then it would have a tire wear problem for street use. If you set it up for street use then a well designed IRS should be able to outperform it AND get good tire wear on the track (or street :roll:

I'm also still wondering what handling advantage this solid axle would have over a 1908 thru 1948 Ford axle set up with 5 link positioning instead of the wishbone.

But it will be interesting to see if a preset [static] camber will be better than an IFS that is purpose designed to correct various cornering loads, roll etc.

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PostPosted: June 8, 2012, 11:53 pm 
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john hennessy wrote:
but i would prefer a beam axle with cart springs over your design, even if it was made of wood.


:lol: Love it, keep them coming!

john hennessy wrote:

to use your word again "eat shite, a million flys can't be wrong"


Ironic that I just started a thread about parallel 4 link rear ends, a million flys are also wrong on that one Louie.

I'll just get my can of Mortein .. http://www.youtube.com/watch?v=QcO2UlIMkpo

olrowdy_01 wrote:

Yes, you could preset this solid axle design to have good high speed cornering but then it would have a tire wear problem for street use. If you set it up for street use then a well designed IRS should be able to outperform it AND get good tire wear on the track (or street :roll:

I'm also still wondering what handling advantage this solid axle would have over a 1908 thru 1948 Ford axle set up with 5 link positioning instead of the wishbone.

But it will be interesting to see if a preset [static] camber will be better than an IFS that is purpose designed to correct various cornering loads, roll etc.


Yeah, nah - respectfully, like John above you, you have no idea how my beam works. I suggest you either go back and read my post on it or wait a few more days when an article is coming out on it that will make it a bit more clear.

It is a lightweight, semi independent beam that has full caster functionality (side to side independent) including caster induce camber in steer.

You are taking the "flat footprint" too literal as well, it is a reference to keeping both wheels behaving properly unlike this for example ..

Image

and more like this ...


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super.jpg [ 126.83 KiB | Viewed 1271 times ]
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PostPosted: June 9, 2012, 3:30 am 
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olrowdy_01 wrote:
I'm more wondering why one would want to "maintain a flat footprint" (keep a constant camber, ignoring caster gain which most [all] front suspensions have) when it is commonly agreed upon that modern tires have more cornering force with varying cambers depending on the cornering forces created by during high speed cornering.

Yes, you could preset this solid axle design to have good high speed cornering but then it would have a tire wear problem for street use. If you set it up for street use then a well designed IRS should be able to outperform it AND get good tire wear on the track (or street :roll:

As much as I believe that the advantages of a well designed double wishbone setup will generally outweigh the disadvantages relative to a beam axle, if you look at the geometry on most implemented double wishbones I think you'll find that the selected camber gain in roll does not change 1:1 with the body roll angle such that there is a net loss of (negative) camber on the loaded side, and a net gain of (negative) camber on the unloaded tire...Which is actually the opposite of what would happen in a perfect world where every suspension decision wasn't a compromise. In such a case the beam axle would actually be able to run less static camber to achieve the same loaded tire camber angle, better unloaded tire camber angle, better straight line traction due to no (negative) camber gain in compression combined with the lower static camber value, and more even tire wear again due to less required static camber. So yes, the beam axle can have its own advantages over double wishbones in certain regards too.

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Last edited by Driven5 on June 13, 2012, 4:37 pm, edited 1 time in total.

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PostPosted: June 9, 2012, 9:24 am 
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/\ /\

It's delightful when I see someone "gets it".

I have real issues ahead of me as the moment "beam" is mentioned everyone immediately see's a "1908 thru 1948 Ford axle" ...

Besides the supermodified car pictured above, look at the attitude of the 4 wheels of this 1953 vehicle with twin beams, ie: all perpendicular to the road...

Attachment:
kurtis drift.JPG
kurtis drift.JPG [ 48.53 KiB | Viewed 1257 times ]


Of course the Super and this Kurtis are under-developed and I have merely set out to cure those ills. Those ills primarily being caster loss in dive (also camber loss in roll), no ability to seperate side to side caster for individual wheel control and of course weight. I have cured all of these, it's just the steering that's holding me back.


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PostPosted: June 9, 2012, 12:48 pm 
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cheapracer wrote:
olrowdy_01 wrote:
Yes, you could preset this solid axle design to have good high speed cornering but then it would have a tire wear problem for street use. If you set it up for street use then a well designed IRS should be able to outperform it AND get good tire wear on the track (or street :roll:

I'm also still wondering what handling advantage this solid axle would have over a 1908 thru 1948 Ford axle set up with 5 link positioning instead of the wishbone.

But it will be interesting to see if a preset [static] camber will be better than an IFS that is purpose designed to correct various cornering loads, roll etc.
Yeah, nah - respectfully, like John above you, you have no idea how my beam works. I suggest you either go back and read my post on it or wait a few more days when an article is coming out on it that will make it a bit more clear.

Also respectfully,
Firstly, I am used to seeing the reason or advantages presented for a new design over an existing design when presenting something new. That's why I keep asking what advantage your axle has over any other solid axle (no matter what you call it). Other than built in adjustability the end result is still a solid axle in usage. Real solid axles can be adjusted by bending but are still solid axles when you are done

More importantly, I believe I have an excellent idea of how your axle works. In affect you've taken a 1908 Model T axle, inserted a swivel at the lower end of the king pin, installed a diagonal (preset-adjustable length) strut from the top of the king pin to a point on the solid axle, replaced the wishbone with 4 links to the chassis, added a pan hard (or something similar) to control lateral movement of the axle in relation to the chassis and called the whole thing a "semi-independent" suspension.


It is a lightweight, semi independent beam that has full caster functionality (side to side independent) including caster induce camber in steer.

ALL front "axles" (including 1908 to 1948 Fords) whether solid or otherwise with caster have caster induced camber change in steer (for better or worse).

I contend that as long as you have the axle connecting the kingpins and the camber is fixed that the suspension is not semi or otherwise independent any more than a 1908 Ford. If one wheel moves vertically due to bounce/droop the other wheel is directly affected by the change to the bounced wheel.

Now if you can get the camber rods to ignore opposite side changes and automatically set the camber due to g forces you'd have something! :)


You are taking the "flat footprint" too literal as well, it is a reference to keeping both wheels behaving properly unlike this for example .. [snip]
OK let's take the strict definition.

Define Flat:
Adjective, Having a surface without slope, tilt in which no part is higher or lower then another.
-------------

Now let's see where I got this erroneous idea about flat footprint.

Your post of 7/1/2010
"Turning left only has nothing to do with tyre contact patch for a beam as both sides are flat 99% of the time but ...."

Your post of 7/2/2010
"Beams can offer flat footprint out of the box 95% of the time regardless of speed and conditions. ......"

You post of 12/30/2011
"It doesn't need camber correction because the 2 tyres maintain a flat footprint."

Your post of 6/9/2012
"Besides the supermodified car pictured above, look at the attitude of the 4 wheels of this 1953 vehicle with twin beams, ie: all perpendicular to the road... "

I see no mention of "Behaving properly". I do see "flat footprint" or perpendicular etc.
____________________________________________________

As far as caster induced camber change ....

Your post of 6/27/2011 (Responding to my comment that camber is preset on a solid axle vs caster induced camber change.)
"It most certainly does compensate for it via using caster. You turn the steering and you gain neg camber. The problem with a solid beam is that same "neg camber giving caster" also at the same applies the incorrect amount of camber to the inside tyre and while not as important does take away some of the beam's advantage."

Your post of 12/3/2011 (Describing set up of the semi independent beam axle.)
"It most certainly does compensate for it via using caster. You turn the steering and you gain neg camber. The problem with a solid beam is that same "neg camber giving caster" also at the same applies the incorrect amount of camber to the inside tyre and while not as important does take away some of the beam's advantage."

The exact same conditions that the 1908 to 1948 Ford axle has if we ignore bounce/droop at this point. And in addition (as we both know) the caster induced change is not always the correct change for all cornering conditions. As an example look at the solid axle camber angle at full steering wheel lock at low speeds or even sitting still.

As I see it, your design is an easily adjustable -solid- front axle. But in affect still a solid front axle. The same as a 1908 Ford axle.

Lighter in weight? Well let's see,
1. You've got four links vs the 4 upper/lower A arms
2. You've got two additional swivels
3. You've got two additional camber setting links, brackets etc
4. And then there's that long axle.

I would imagine that one could affect the unsprung weight much more by careful selection of the brakes, uprights, rims, tires etc. And that would work for an IFS or a light solid axle design.

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PostPosted: June 9, 2012, 3:04 pm 
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I'll mention it again on my way to bed now that Canada F1 Qualy is finished ...

You do not comprehend why it has individual caster control nor how it is applied.

You do not comprehend why it has individual camber control nor how it is applied.

You don't understand how my beam works. You don't understand it's advantages - seriously, you just don't get it, but you will soon...

I mentioned to you that an article is coming out shortly on it and you'll have to excuse for not writing it all out now at 2am, you'll just have to wait a few days.

So, good night :)

PS: "flat footprint" is a common term in the tyre and race industry.
PPS: The effort you have gone to over semantics is bizzare.


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PostPosted: June 9, 2012, 3:09 pm 
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Footnote;

olrowdy_01 wrote:
Now if you can get the camber rods to ignore opposite side changes and automatically set the camber due to g forces you'd have something!


Well I guess I have "something!" then.


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PostPosted: June 10, 2012, 9:43 am 
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cheapracer wrote:
Footnote;

olrowdy_01 wrote:
Now if you can get the camber rods to ignore opposite side changes and automatically set the camber due to g forces you'd have something!


Well I guess I have "something!" then.


Is it contagious? Have you tried penicillin? :rofl:
:cheers:

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PostPosted: June 10, 2012, 10:40 am 
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There has been some comparison to the Lotus 58 double beam F2 car elsewhere which I refute. The Lotus system has excatly what is wrong with most beams and is opposite to what my system offers.

Whereas the Lotus offers caster loss in dive and bump as well as side to side caster being locked into acting in unison, my system offers caster gain in dive and bump as well as total side to side independent caster operation.

It also strutually superior to a typical beam because, as you can see, the upper link is directly connected to the upright and the lower link is just short of connecting to the upright as well.

GonzoRacer wrote:
Have you tried penicillin?


Yup, the Doctor mentioned I would feel a little prick ...

Anyway, to save some obvious frustration, today I removed the top trailing link front bolt and independently operated the caster by hand. It's not rocket science, just as a top arm on an IFS controls camber laterally, my "top arm" (trailing link) controls caster longitudinally. There is a difference in length between the upper and lower trailing links just like

The short lateral camber link is free to move longitudinally with the upright as you can see but can not move laterally - I think this is the motion people don't seem to understand is available thinking it is all locked solid there ..

Attachment:
LH beam upright.jpg
LH beam upright.jpg [ 57.14 KiB | Viewed 1222 times ]


Oska winner here ... (click on to see video)
Image

Note I am moving it about 6" whereas in actual operation it would move only 1/2".

Below demonstrates the caster gain....

Image
Image

So there you have, obviously very similar to a Morgan designed, wooden, sliding pillar, solid axle, made in 1908 by Ford.


Last edited by cheapracer on July 8, 2012, 12:42 pm, edited 6 times in total.

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